Lightning arrester



y 21, 1929- A. L. ATHERTON 1,714,255

LIGHTNING ARRBSTER Filed Feb. "7, 1927 WITNESSES:

INVENTOR fYf/Ec/L. zQf/verfon.

7 ATI'ORNEY Patented May 21, 1929.

UNITED STATES ALFRED L. ATHERTON, OF YENN TOWNSHIP, ALLEGHENY COUNTY, PENNSYLVANIA.

ASSIGNOR TO WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A COR- PORATION OF PENNSYLVANIA.

LIGHTNING ARRESTER.

Application filed February 7, 1927. Serial No. 166,812.

My invention relates tolightning arr-esters and especially to new and improved casings for the same.

More particularly, my invention relates to a novel lightning arrester construction which comprises a plurality of unit devices which are arranged to facilitate assembling any number thereof.

An object of my invention is to provide acompact and inexpensive assembly of units I which is strong and rigid.

Still another object of my invention is to provide a casing which is particularly adapted to lightning arresters of the ,autovalve type or any similar type having a plurality of discharge paths. f

In the accompanying drawing,

Fig. 1 is a view, partly in'elevationand partly in section, of an arrest-er unit embodying my invention, and

Fig. 2 is a view, in side elevation, of a complete arrester assembly embodying my invention. v A substantially cylindrical casing member 3 of porcelain is provided with four cylindrical, parallel, and axially extending perforations or chambers 4: open at both ends- Disposed in each chamber is a stack of discs 5, suchas are described in the Slepian Patent N o. 1,509,493,issued September 23, 1924.

Disposed in the upper end ofeach chamher, is a spring 6 for maintaining the discs under a compressional stress. A flexible shunt 7 of good conducting material is pro vided for by-passing current around the spring.

A base member 8, comprising two substantially circular metallic plates 9 and 10 of difi'erent diameters, is secured to the bottom end of the casing member. The smaller plate 9 fits the bottom end of the casing member to retain the discs within the chambers and is provided with eight perforations spaced at equal distances around the circum ference thereof. The larger plate 10, or base member proper, is provided with similarly disposed perforations, whereby the two platesmay be fastened together, as by means of bolts 11. The plates are so joined that a substantially annular opening 12 is provided therebetween. The purpose of this opening will be hereinafter set forth.

The larger plate 10 has an annular projeeting'portion13 disposed parallel to its by providing an annular the casing member and is held in place ,ber is not vertical axis and arranged to fit over the end of the porcelain casing member 3, theredepression or pocket ll therebetween. A quantity of Portland cement 15 is disposed in the pocket, thereby securing the base member 8 to the bottom of the casing member 3.

After the larger plate 10 has been cemented to the porcelain casing member 3, a cork gasket 16 is applied to the bottom end of bv drawing up the smaller plate 9 toward the larger plate 10.

The cork gasket 16 is compressed to one half of its original thickness, thereby making it substantially impervious to water. It has been found that the cement which sccures the base member to thecasing memsufliciently impervious to keep water from entering the chambers. Therefore, the cork gasket has been provided to accomplish the result mentioned above.

The annular opening 12, disposed between the two plates 9 and 10 that constitute the base member 8, serves as an outlet for any moisture which may enter the annular pocket 14 and seep through the cement 15. The inner surface of the upwardly pro Jecting portion 13 of the base member is corrugated, as shown at 17, to make the adhesion' of the cement more perfect. The outer surface of the lower end 18 of the easing member is either sanded 0r knurled for the same reason. A'metallic, circular cap member 20, hava projecting portion adapted to fit the upper end ofthe casing member, is mountc'd'thereupon, thereby providing an annular pocket or depression 21. The cap member 20 is cemented to the upper end of the casing member 3, with a cork gasket 22 interposed between the end surface of the casing member and that portion of the cap member adjacent thereto. The gasket 22 is maintained under compression similar to the lower gasket 16, and although it may be injured somewhat during the cementing of the cap, it does not need to be so impervious to water as the lower gasket 16, and it serves the important function of cushioning any irregularities.

A quantity of Portland cement 23 is disposed in the annular pocket 21, completely r filling it. The inner surface 2% of the 'projecting portion of the cap member is corrugated, and the surface of the end portion 25 of the casing member is sanded or knurled,

' thereby'providing better adhesion between the cement and themembers joined by it.

Thecap member 20.1sprov1ded with a central portion 26 which is slightly elevated and which slopes gradually toward the outer portions of the cap member. This crowning of the top casting, together with the fact that there is no perforation in the same, insures that no moisture can enter into the arrester unit through the top.

The cap and base members are provided withlike thickened portions or pads 26 and V 27-,respectively, which are easily mach ned to provide" a level surface, and which provide, a spacerfor the 'eXitof water, in case any water should seep through the cement 15. The pads 26 ancl 27 are perforated, as indicated at 28, to provide means for l'l'lOlll'l h".

ling. the base member of one unit upon the cap member of anotherunit'and fastening them together by means ofbolts 29, as shown inFig.2." 4

The casing member 3 is provided'with a downwardly and outwardly projecting skirtlike' portion 30. This portion provides an increase int-he creepage distance bet-wen the cap and"base members. In addition, this portion provides a protection against moisture entering the chambers by way of the annular pocket 1%. i

Referring to t 1g. 2, a complete lightningarrester assembly is shown comprising eight of thef unit discharge devices described above. The said devices are mounted serially in a column, one upon the other, and fastened together by the bolts 29 projecting through the similarly disposed openings 28 in adjacent caps 20 and bases 8. The lower end of the column of unit discharge devices is mounted upon a base 32 WhlCll'lS electrically connected to the ground. The up-' per end of the column is provided with a spark-gap electrode 33. line potential spark-gap electrode 34: is disposed at, a dis tance from the first electrode and both are protected by a canopy or hood 35 resting, at

one end,on the top of the lightning-arrester column. Y a j The line-potentialelectrode 34 is mounted upon a frame-work structure 36 and'insulated from the ground andfrom the hoodby means of superpositioned insulators 37 andv The lme conductor 39,,

38, respectively,

7 leading to the line wiich the lightning arinsulators 87 and 38.

rester is to protect, is mounted upon the frame-work '36 at a point between the said It is apparent that the type of unit-casing construction herein described is particularly adapted to a lightning arrester of the H autovalve type or of any similar typewhich comprises a plurality of unit discharge devices mounted one upon another. By my in vention, I am able to mount a plurality of these unit discharge devices in a column which will be strong andrigid, withoutsaik 'rificin the ease with which theyrmay be assembled. o r My invention provides a means for assembling'aplurality of unit discharge devices which does not involve disposing fastening members of a conducting material within the porcelain casings, my fastening members 29 being disposed outside of" the casings 3. This feature is particularly desirable, since I am able to obtain reater insulatin "uale b r O ities in smaller casings than heretofore.

'Heretofore, difficulty has been GXPQIT.

encedin joining a plurality of unit discharge devices, owing to the fact that the brittle character of the porcelain constituting the casings was a serious detriment to the mechanical strength of a column of such devices. My invention, utilizing all-metal joints, provides column having greater strength at the points at'which' unit discharge devices are joined; 7

Another important feature of my inven tion is the elimination of alli'nsulating ma terials except porcelain. This will be recogmzed as aparticular advantage because of.

the qualities of its long life, its ability to permanently withstand weather changes in temperature, and its' imperviousness to moisture, which are superior to the characteristics of such fibrousinsulating members as micartatubes and wooden supporting rods Although I have described herein a particular embodiment of ,my'invention, I do not wish to be altogether. limited 'to any such specific structure, and Idesire that the .which are standard parts in other high- I voltage arresters on the'market.

appended claims shall 'be accorded the' portion arranged to telescope the end of the casing member thereby closing one set of 3 ends of the chambers, a. quantity of cement disposed between the telescoping portions of the casing member and the base member thereby securing the baseinember to the cas ing member, a gasket interposed betweenthe end surface of the. casingand the face plate of the base adjacent thereto, thereby preventing moisture from, entering the chambers, saidbase member having also an opening therethrough arranged to permit any moisture which permeates the cement to v now out; r

'2. A unit discharge device comprising a casing member having a plurality of discharge paths therethrough, a cap member theretlirough, said annular opening consti- 10 having an annular flange portion arranged tuting a means of draining any moisture to fit over the upper end of the casing memwhich collects between the annular flange ber, said cap member having an elevated portion and the end of the casing adjacent 5 central portion, a base member comprising a thereto.

plurality of members fastened together hav- In testimony whereof, I have hereunto 15 ing an annular flange arranged to fit over subscribed my name this 5th day of Februthe lower end of the casing, said base also ary, 1927.

having a substantially annular opening ALFRED L. ATHERTON. 

